This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A168282 #25 Sep 08 2022 08:45:48
%S A168282 1,6,6,11,11,16,16,21,21,26,26,31,31,36,36,41,41,46,46,51,51,56,56,61,
%T A168282 61,66,66,71,71,76,76,81,81,86,86,91,91,96,96,101,101,106,106,111,111,
%U A168282 116,116,121,121,126,126,131,131,136,136,141,141,146,146,151,151,156
%N A168282 (10*n + 5*(-1)^n - 1)/4.
%H A168282 Vincenzo Librandi, <a href="/A168282/b168282.txt">Table of n, a(n) for n = 1..1000</a>
%H A168282 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (1,1,-1).
%F A168282 a(n) = 5*n - a(n-1) - 3 for n>1, a(1)=1.
%F A168282 a(1)=1, a(2)=6, a(3)=6; for n>3, a(n) = a(n-1) +a(n-2) -a(n-3). - _Harvey P. Dale_, Jun 17 2013
%F A168282 From _Bruno Berselli_, Sep 16 2013: (Start)
%F A168282 G.f.: x*(1 + 5*x - x^2)/((1+x)*(1-x)^2).
%F A168282 a(n) = A168457(n)/2.
%F A168282 a(n) = A168278(n) - 1.
%F A168282 a(n) = ( A168459(n) + 1 )/2. (End)
%F A168282 E.g.f.: (1/4)*(5 - 4*exp(x) + (2*x - 1)*exp(2*x))*exp(-x). - _G. C. Greubel_, Jul 16 2016
%t A168282 RecurrenceTable[{a[1]==1,a[n]==5n-a[n-1]-3},a,{n,70}] (* or *) LinearRecurrence[{1,1,-1},{1,6,6},70] (* _Harvey P. Dale_, Jun 17 2013 *)
%t A168282 Table[5 n/2 + 5 (-1)^n/4 - 1/4, {n, 70}] (* _Bruno Berselli_, Sep 16 2013 *)
%t A168282 CoefficientList[Series[(1 + 5 x - x^2) / ((1 + x) (1 - x)^2), {x, 0, 70}], x] (* _Vincenzo Librandi_, Sep 16 2013 *)
%o A168282 (Magma) [n le 1 select (n) else 5*n-Self(n-1)-3: n in [1..70]]; // _Vincenzo Librandi_, Sep 16 2013
%o A168282 (PARI) a(n)=5*n/2+5*(-1)^n/4-1/4 \\ _Charles R Greathouse IV_, Oct 16 2015
%Y A168282 Cf. A016861, A168278, A168457, A168459.
%K A168282 nonn,easy
%O A168282 1,2
%A A168282 _Vincenzo Librandi_, Nov 22 2009
%E A168282 New definition by _Bruno Berselli_, Sep 16 2013